Armor of Fafnir: Blood Armor of the Evil Dragon (悪竜の血鎧アーマー・オブ・ファヴニール,Āmā obu Favunīru: Akuryū no Chiyoroi?) is an ability that embodies and re-enacts the legend of Siegfried bathing in dragon-blood from Fafnir, granting him a dragon's body with invulnerability that made all weapons ineffective against him during his life. Having swallowed the blood as well, it circulates throughout his body and affects his organs, later affecting Sieg upon transplanting his heart into the homunculus. Dyed brown with Fafnir's blood and composed of dragon scales, his skin is compared to steel in strength, unable to be wounded by either weapons or magic except with the greatest of attacks. Called invincible in life until struck down by his friend, it caused him to lose the joy of battle because it did not allow him to feel the sensation of struggling against death, his body proofed against any and all attacks making it possible to slaughter enemies without much thought like simple labor.

His skin is able to cancel physical attacks and magic equivalent to B-rank or lower, allowing him to take hits to vital areas without worry. It requires attacks of A-rank and above to harm him, but they register as damage only after the defensive values of an amount equal to B-rank are subtracted from them. When facing Noble Phantasms wielded by proper heroes, it gains defensive values equivalent to B+ rank. Even without an A-rank attack, it is possible to pierce it under special circumstances. Lancer of Red's spear possesses power proportionate to an A-rank attack even without activating it as a Noble Phantasm, and while that would not be enough on its own to land a blow, Lancer's immense physical strength and transcendent technique allow for a destructive force great enough to cause harm. The wounds he inflicts are shallow due to the circumstances, and even though they number over seventy on vital points like arteries and his forehead, healing magecraft from his Master restores Siegfried to normal immediately due to their minor damage. Due to this Noble Phantasm, his Magic Resistance skill has been lost.[1]

Due to a linden leaf sticking to him during the bathing process, he has a leaf-shaped mark upon his back that marks his only weakness. His back does not gain defensive values, allowing even the weakest of Servants to kill him by striking him there, and he is unable to conceal it.[2] Due to his fame, it will become the primary target should his identity be found out by others, causing Gordes, his Master, to act with as much caution as possible to avoid revealing his identity.

Personal Skills
■ Golden Rule: C-
A life in which money is fated revolve around.
Due to the Nibelung treasure promised a life untroubled by money, but Luck is Rank-Down.

Noble Phantasms
■ Armor of Fafnir: Blood Armor of the Evil Dragon
Rank: B+
Type: Anti-Unit
Range: -
Maximum number of targets: 1 person
A Noble Phantasm embodying the story of his bath in the blood of a dragon. B-rank equivalent physical attacks and magic are nullified. Attacks of A-rank and above register as damage after defensive values of an amount equal to B-rank are subtracted from them. If facing a Noble Phantasm used by a proper hero, it gains defensive values equivalent to B+. However, his back, which was not bathed in the blood, does not gain defensive values, and he is unable to conceal it.

■ Balmung: Phantasmal Greatsword, Felling of the Sky Demon
Rank: A+
Type: Anti-Army
Range: 1-50
Maximum number of targets: 500 people
A cursed holy blade which had accomplished the feat of dragon slaying.
It also possesses the attributes of its origin, the demonic blade Gram, and will change attributes between holy sword and demonic sword depending on who wields it. The blue jewel of the hilt stores and preserves magic energy (true Ether) from the age of gods, and upon releasing it, emanates a twilight aura. Those with the blood of dragons take additional damage.

Personal Skills
■ Golden Rule: C-
A life in which money is fated revolve around.
Due to the Nibelung treasure promised a life untroubled by money, but Luck is Rank-Down.

Noble Phantasms
■ Armor of Fafnir: Blood Armor of the Evil Dragon
Rank: B+
Type: Anti-Unit
Range: -
Maximum number of targets: 1 person
A Noble Phantasm embodying the story of his bath in the blood of a dragon. B-rank equivalent physical attacks and magic are nullified. Attacks of A-rank and above register as damage after defensive values of an amount equal to B-rank are subtracted from them. If facing a Noble Phantasm used by a proper hero, it gains defensive values equivalent to B+. However, his back, which was not bathed in the blood, does not gain defensive values, and he is unable to conceal it.

■ Balmung: Phantasmal Greatsword, Felling of the Sky Demon
Rank: A+
Type: Anti-Army
Range: 1-50
Maximum number of targets: 500 people
A cursed holy blade which had accomplished the feat of dragon slaying.
It also possesses the attributes of its origin, the demonic blade Gram, and will change attributes between holy sword and demonic sword depending on who wields it. The blue jewel of the hilt stores and preserves magic energy (true Ether) from the age of gods, and upon releasing it, emanates a twilight aura. Those with the blood of dragons take additional damage.